Chocolate Bluetooth

I saw this on eBay for £25 and instantly thought it might be worth a punt…

Should have probably looked up how to Bluetooth with a zynthian first.

Running ‘bluetooothctl’ on the command line seems to do diddly squat.

Reckon I can use this as a remote anyway?

There are two steps with BT midi. First, connect the BT to the device using the standard procedure like:
https://www.raspberrypi.org/forums/viewtopic.php?t=214373

Make sure you trust it. Then you will have created a MIDI device that will re-connect. From there you need to connect the stream to zynth, but you need to do it via the OS MIDI thru port like this:

root@zynthian:~# aconnect -l
client 0: 'System' [type=kernel]
    0 'Timer           '
    1 'Announce        '
	Connecting To: 128:0
client 14: 'Midi Through' [type=kernel]
    0 'Midi Through Port-0'
	Connecting To: 128:0[real:0]
	Connected From: 128:0
client 16: 'f_midi' [type=kernel,card=0]
    0 'f_midi          '
client 129: 'UD-BT01' [type=user,pid=695]
    0 'UD-BT01 Bluetooth'

Then you need to connect the device (the UDBT01 in this example) to the MIDI through port:

root@zynthian:~# aconnect 129 14

and you get this:

root@zynthian:~# aconnect -l
client 0: 'System' [type=kernel]
    0 'Timer           '
    1 'Announce        '
	Connecting To: 128:0
client 14: 'Midi Through' [type=kernel]
    0 'Midi Through Port-0'
	Connecting To: 128:0[real:0]
	Connected From: 128:0, 129:0
client 16: 'f_midi' [type=kernel,card=0]
    0 'f_midi          '
client 129: 'UD-BT01' [type=user,pid=695]
    0 'UD-BT01 Bluetooth'
	Connecting To: 14:0

That should work. Unfortunately, it doesn’t re-connect the MIDI port on re-boot.

Of course, you could probably just connect the USB cable…

Gonzo

I am not even able to get that far… oh dear

systemctl enable --now bluetooth

This is what mine looks like

root@zynthian:~# systemctl status bluetooth
● bluetooth.service - Bluetooth service
   Loaded: loaded (/lib/systemd/system/bluetooth.service; enabled; vendor preset: enabled)
  Drop-In: /etc/systemd/system/bluetooth.service.d
           └─01-disable-sap-plugin.conf
   Active: active (running) since Mon 2022-03-21 04:50:23 GMT; 1 months 4 days ago
     Docs: man:bluetoothd(8)
 Main PID: 626 (bluetoothd)
   Status: "Running"
    Tasks: 1 (limit: 2061)
   Memory: 2.1M
   CGroup: /system.slice/bluetooth.service
           └─626 /usr/lib/bluetooth/bluetoothd --compat --experimental --noplugin=sap

Mar 21 04:50:22 zynthian systemd[1]: Starting Bluetooth service...
Mar 21 04:50:23 zynthian bluetoothd[626]: Bluetooth daemon 5.50
Mar 21 04:50:23 zynthian systemd[1]: Started Bluetooth service.
Mar 21 04:50:23 zynthian bluetoothd[626]: Starting SDP server
Mar 21 04:50:23 zynthian bluetoothd[626]: Excluding (cli) sap
Mar 21 04:50:23 zynthian bluetoothd[626]: Bluetooth management interface 1.14 initialized
Mar 21 04:50:23 zynthian bluetoothd[626]: Failed to set privacy: Rejected (0x0b)

what if you do dmesg | grep -i blue

dmesg | grep -i blue returns nothing

This was a power issue. I guess the Bluetooth shuts down if there isn’t enough juice?

Hi @MrBroccoli, I was looking into one of these (superlooper is begging for a foot controller!), and remembered this thread. Did you got it to work in the end, via Bluetooth or even just via USB cable? (Assuming zynthian can power and interface midi with the usb cable, or is that not the case?)

Sorry, I got sidetracked with other things and have not got back to this yet.

Nothing to be sorry about!
According to this, midi can flow through USB and also using the TRS (sacrificing an expression pedal). I think I’ll just go for one and report back (might take a while from AliExpress). Stay tuned!

2 Likes

Finally, I got the (very small, exactly what I wanted for my limited floor space) Chocolate / M-VAVE foot controller. Only did a few experiments, and the answer to my question seems to be negative - USB is limited to upgrading its firmware and to recharge the device.
Didn’t try bluetooth into Zynthian directly (maybe next weekend). But it’s easy to configure from the App (tried the desktop Mac app as well as Android, both connected with no issues and respond well), so my Ableton Live seems to like that. My thinking is that this is a good fallback as I can then send the MIDI signal to Zynthian, in case I can’t get it to work with Zynthian on its own.
Also an option would be to use the Pedal port as a TRS MIDI out (but then I’d loose the Pedal support that is useful). I’ll have a think / experiment and balance this to the fact that having Chocolat linked to Ableton allows me to use it with more than just the Zynthian.

First impression is positive though - considering how cheap it is.

Next post shall be once I can get SuperLooper to respond to it and actually use it to, well, play musi - eerm, sounds!